Gastric acidity suppression is recommended for critically ill patients,1 with strong clinical evidence for efficacy, particularly in mechanically ventilated patients. Acid-suppressive agents such as proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RA) are thought to decrease the risk of acute gastrointestinal tract (GI) hemorrhage from stress-induced ulcers. However, the suppression of gastric acidity has been shown in several observational studies to lead to higher rates of pneumonia and Clostridium difficile infection (CDI) in settings other than the intensive care unit (ICU).2,3 It is unclear whether these findings extend to the ICU, where nosocomial infections entail considerable mortality and costs.